One thing to try (on Steam) would be to go to "Properties" for Celeste. Go to "Betas" -tab and choose "opengl - opengl". You may need to uninstall and reinstall Everest from Olympus so it knows to open the right version for vanilla.

Hi! So just making sure: Do you want to see livesplit at all times yourself or for it to just be visible in the video? For video we usually window capture it in a recording software and put it on top of the gameplay video. Also make sure to follow these guidelines when setting it up -> https://imgur.com/a/celeste-footage-guidelines-pFKo3Ni

For seeing it on top of your actual game I don't have a solution for, but I also wouldn't recommend it. You will most likely end up blocking many room exits and crucial parts of the game from yourself. Recommending either windowed mode or just tabbing out and checking splits in between levels.

Thank you! I don't really do much on Youtube though. I'm more of a Twitch streamer.

Haha, good job! I wasn't really expecting this. I felt a bit sorry for taking your record like 2 weeks after you got it, but I'm glad it made you fight for it.

I may or may not return for this, but you can hold the title for now. I need to set some pb's in the actual Celeste now. GG!